Natural Killer (NK) cells have been previously reported to both activate and inhibit B cell functions. This regulation is not well understood and depends both on the activation state of the NK cell and/or the B cell. In order to better understand this regulation, a binding methodology has been established between the NK and B cell where limited interaction occurs and the cells are then separated by physical shear and magnetic bead depletion. Using this novel procedure, the mechanism of Ig regulation by NK cells is under study.